Digest for sci.electronics.repair@googlegroups.com - 25 updates in 5 topics

Fred McKenzie <fmmck@aol.com>: Feb 20 12:51PM -0500

In article <0i9p6eh1b8ngk1tqfctn0csof5ta8ekgjb@4ax.com>,
 
> Is there a fix; is it a loose connection, dust or
> grit in the works? Should I just flush it out.
 
> Otherwise the radio works well.
 
Peter-
 
You have a number of good suggestions above.
 
While you in the radio, check to see if there is a capacitor coupling to
the volume control. It is possible that a leaky coupling capacitor is
causing a DC current to flow in the volume control. Such a current can
cause any "scratchiness" to be made worse.
 
Fred
Ian Jackson <ianREMOVETHISjackson@g3ohx.co.uk>: Feb 20 11:03PM

In message <6c49be26-2a37-465f-bc02-5c09c0ca676a@googlegroups.com>, Phil
Allison <pallison49@gmail.com> writes
 
>> John :-#)#
 
> ** Wot a bloody lunatic.
 
>.... Phil
 
I feel that the horrors of WD40 are greatly exaggerated. Since I lost my
tube of 'the real thing' (about 40 years ago) I've occasionally used
WD40 as a switch and volume control cleaner - and I've never had a
problem with it.
--
Ian
Phil Allison <pallison49@gmail.com>: Feb 20 03:39PM -0800

Ian Jackson wrote
:
 
> >.... Phil
 
> I feel that the horrors of WD40 are greatly exaggerated.
 
** The name is WD40 - not WMD40.
 
 
 
> WD40 as a switch and volume control cleaner - and I've never had a
> problem with it.
> --
 
 
** Nor has anyone else.
 
 
... Phil
"pfjw@aol.com" <peterwieck33@gmail.com>: Feb 21 04:51AM -0800

On Tuesday, February 19, 2019 at 8:52:40 PM UTC-5, Phil Allison wrote:
 
> ** Same composition as WD-40 at *many times* the price.
 
Twit:
 
Please note on the description: "Moderate Evaporation", and then try to learn something not covered by your closely held beliefs. Or are you one of those who wishes to have it both ways?
 
Peter Wieck
Melrose Park, PA
Mark Lloyd <not@mail.invalid>: Feb 20 11:33AM -0600

On 2/19/19 5:58 PM, micky wrote:
 
[[snip]
 
> I can't use radios with electronic tuning because with a timer that
> turns the power off and on, when it comes on, the radio doesn't start
> until someone pushes a button.
 
I also find that "power amnesia" to be an annoyance. For most of the
settings, modern devices use permanent memory. Often, they exclude the
"power' switch.
 
BTW, For TVs, I notice that many smaller ones will remember, and can be
used with a timer. Bigger TVs are power amnesiacs.
 
--
Mark Lloyd
http://notstupid.us/
 
"Common sense is what tells you that the world is flat."
Mark Lloyd <not@mail.invalid>: Feb 20 11:37AM -0600

On 2/19/19 8:02 PM, Rod Speed wrote:
[snip]
 
>> turns the power off and on, when it comes on, the radio doesn't start
>> until someone pushes a button.
 
> They arent all like that. Just replace the radio with a better analog one.
 
If it doesn't come on after a power interruption, that sounds like a
defect (unless this was an OPTION you set). I wish they'd put that
information on the box and in ads.
 
BTW, another piece of useful (but often missing) information is latency
of an internet connection. This is often more important than speed.
 
--
Mark Lloyd
http://notstupid.us/
 
"Common sense is what tells you that the world is flat."
Mark Lloyd <not@mail.invalid>: Feb 20 11:45AM -0600

On 2/19/19 10:27 PM, micky wrote:
 
[snip]
 
>> Have your timer turn the TV on/off. Leave cable box set to music channel.
 
> If the timer provides power to the TV, someone has to press the TV's
> on/off button.
 
I have found this to be true with larger TVs, but not with smaller ones
(the largest I have without the problem is 22-inch). However, they don't
put this on the box and any salespeople will probably NOT be able to help.
 
Possibly a very expensive TV might have an option for this.
 
 
--
Mark Lloyd
http://notstupid.us/
 
"Common sense is what tells you that the world is flat."
Mark Lloyd <not@mail.invalid>: Feb 20 11:47AM -0600

On 2/19/19 10:39 PM, micky wrote:
 
[snip]
 
> Digital radios won't work here. They all afaik have a separate
> momentary-on on/off switch.
 
Having a momentary switch is not the problem, it's that without power it
forgets the setting of that electronic switch.
 
[snip]
 
--
Mark Lloyd
http://notstupid.us/
 
"Common sense is what tells you that the world is flat."
Diesel <nobody@haph.org>: Feb 21 02:45AM

"\"Retired"@home.com
news:zYGdnTvUQI3ZLvHBnZ2dnUU7-SHNnZ2d@giganews.com Wed, 20 Feb 2019
01:54:12 GMT in alt.home.repair, wrote:
 
> have music only channels ? Our Xfinity/Comcast does.
 
> Have your timer turn the TV on/off. Leave cable box set to music
> channel.
 
While a timer could be used to turn a modern tv off, it's highly
doubtful you can turn it back on with the timer. All tvs I've seen in
the past say, ten years have standby modes. If you connect them to AC,
they don't just turn on, you still have to press a button. You can't
really tape the button down or short it out in most cases either,
because it'll most likely do one of two things if you did:
 
(a) stay off all the time
(b) turn on, but go back to stand by a short time later, because you
aren't letting go of the button
 
I seriously doubt it would come out of standby and remain on if you the
button remained pressed. You'd need an older tv that had a real power
switch that actually did turn it on or off, not one with a standby or
sleep mode.
 
 
--
Radioactive halibut will make fission chips.
Diesel <nobody@haph.org>: Feb 21 02:45AM

micky <NONONOmisc07@bigfoot.com>
news:oslp6ehjgeororp691fq6rk5bknptqiej8@4ax.com Wed, 20 Feb 2019
04:39:56 GMT in alt.home.repair, wrote:
 
>>only with the old radios tho, not modern digital ones.
 
> Digital radios won't work here. They all afaik have a separate
> momentary-on on/off switch.
 
That isn't restricted to a digital radio. It's any device that has a
sleep mode or standby power mode. IE: anything that doesn't have a real
power switch. The momentary push button switches on modern tv sets
aren't controlling high voltage ac mains directly; they're telling
another circuit board that's using a small amount of power that it's
okay to close a relay to bring the main power board online from the ac
mains. And it'll hold the relay closed until you press the little
button again, which opens the relay and resumes sleep/suspend/standby
mode.

 
 
--
Out of Taglines, Please Order More
Diesel <nobody@haph.org>: Feb 21 02:45AM

Mark Lloyd <not@mail.invalid> news:tbgbE.6149$Dv6.3095@fx06.iad Wed,
20 Feb 2019 17:33:12 GMT in alt.home.repair, wrote:
 
 
> I also find that "power amnesia" to be an annoyance. For most of
> the settings, modern devices use permanent memory. Often, they
> exclude the "power' switch.
 
Most of the time, the power switch is controlled by another board
entirely that's mostly a small transformer, a few circuits, a relay
and access to the hot leg of the ac mains that it passes along via a
closed relay to the rest of the set that does the real work. When you
push the button to turn the tv off, it opens the relay. When you want
it on, it closes the relay. The remote on the tv is doing the same
thing. Sometimes, the IR LEDs are on the smaller standby board and
other times it's located on their own boards wired to it, or might be
sitting on the actual mainboard of the set, but electrically
connected only to the standby board; it just has a physical residence
on the mainboard.
 
So, there's nothing for it to memorize, and no way to enforce the
memorization if it did, as the standby board is entirely reliant on
human interaction for relay open/close.
 
The only exception are sets that have additional circuitry to trip
the standby board into closing the relay with pulse signal; this
requires additional circuitry on the standby board as well as
mainboard of the set, wiring, additional coding frontend/backend,
and, space to store the last known 'setting' to enforce when the
standby board has access to ac mains power.
 
The additional circuitry on the standby board serves to provide a
limited amount of power to the mainboard without closing the relay so
the mainboard can pull the last known setting and tell the standby
board to close the relay, if that was the setting. When it closes the
relay, that's when it's connecting ac mains (the hot leg) to the main
power supply that actually runs everything else. The standby board
has it's own power supply that's always hot if the set is plugged in.
 
 
 
--
Big donkeys, small donkeys, all good to eat.
micky <NONONOmisc07@bigfoot.com>: Feb 20 11:23PM -0500

In alt.home.repair, on Wed, 20 Feb 2019 11:33:12 -0600, Mark Lloyd
 
>I also find that "power amnesia" to be an annoyance. For most of the
>settings, modern devices use permanent memory. Often, they exclude the
>"power' switch.
 
Yes, exactly.
 
>BTW, For TVs, I notice that many smaller ones will remember, and can be
>used with a timer. Bigger TVs are power amnesiacs.
 
I have a small tv but for various reasons, can't use it.
 
I'm set up now, though. Thanks all.
Fox's Mercantile <jdangus@att.net>: Feb 20 11:21PM -0600

On 2/20/19 10:23 PM, micky wrote:
> I'm set up now, though.
 
So, how about after all the flailing around here, you TELL us
what you did/ended up with.
 
--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
devnull <devnull@127.0.0.1>: Feb 21 05:48AM -0500

On 2/19/19 6:58 PM, micky wrote:
> and also a radio, but some radios get so far out of tune, even when I
> don't touch them, that almost nothing comes out, and I'd like the radio
> to continue to play the station clearly.
 
 
 
Are you afraid some border-hoppin' thief is going to steal your stuff?
 
The most effective way to keep the criminals out is to build a wall around your house. Open borders don't work.
George <george@spacely-sprokets.com>: Feb 21 06:32AM -0500

On 2/21/2019 5:48 AM, devnull wrote:
 
> Are you afraid some border-hoppin' thief is going to steal your stuff?
 
> The most effective way to keep the criminals out is to build a wall around your house.  Open borders don't work.
 
Nancy Pelosi has an immoral wall around her compound.  She also has people with guns protecting her home as well.
"pfjw@aol.com" <peterwieck33@gmail.com>: Feb 21 04:26AM -0800

On Thursday, February 21, 2019 at 5:48:33 AM UTC-5, devnull wrote:
 
 
> The most effective way to keep the criminals out is to build a wall around your house. Open borders don't work.
 
All walls around properties do is give the thieves shelter from outside eyes.
All lights do around properties is give thieves light to work with.
 
All that is necessary to prevent thievery is for *your* house to be a little bit tougher than the next house. Much as I do not have to be faster than the bear, just one other person.
 
Dogs work well. And being home at the target time. Given that most burglaries happen between 10:00 am and 2:00 pm - when most people are at work or at school. And in the better neighborhoods, a panel van will drive up, a couple of individuals get out in jump suits and carrying clip-boards. One might set up a power-washer or some such.... you get the picture.
 
In the next township over from us, a truck delivered some cheap furniture, in boxes, and loaded up all the good stuff prior to leaving. Brilliant.
 
Peter Wieck
Melrose Park, PA
"pfjw@aol.com" <peterwieck33@gmail.com>: Feb 21 04:28AM -0800

On Thursday, February 21, 2019 at 6:32:07 AM UTC-5, George wrote:
 
> Nancy Pelosi has an immoral wall around her compound.  She also has people with guns protecting her home as well.
 
 
No, it does not. And the Orange Toad squats behind a fence, not a wall.
 
Peter Wieck
Melrose Park, PA
KenW <ken1943@invalid.net>: Feb 20 03:33PM -0700

Check this page
 
https://electronicsclub.info/transistors.htm
Jeff Liebermann <jeffl@cruzio.com>: Feb 20 09:18AM -0800

On Tue, 19 Feb 2019 23:13:16 -0600, tubeguy@myshop.com wrote:
 
Like this? It has straight sides:
<https://62e528761d0685343e1c-f3d1b99a743ffa4142d9d7f1978d9686.ssl.cf2.rackcdn.com/files/93218/area14mp/image-20150827-378-u7k0in.jpg>
 
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
whit3rd <whit3rd@gmail.com>: Feb 20 12:16PM -0800

> more like a hat, with a brim. Those too vanished. And I recall seeing
> some of the hat shaped types with a point sticking out of the top. I
> always wondered what that point was for???
 
If it was like this
<http://www.oddmix.com/semi/5a_western_el.html>
the 'point' was where the vacuum pump was applied, and the metal case pinched shut.
 
There was no good coating for Ge transistors to keep the surfaces clean, because
Ge doesn't have a strong, stable oxide; paint was too dirty, and sputtering quartz
was expensive. So, seal it in a vacuum was one solution. There were
others (one gizmo I cut open had a kind of goo/gel blobbed over the germanium part).
 
TO-18 and TO-5 and TO-39 cases might have been e-beam welded at the top/base seam,
which could also hold a vacuum.
bitrex <user@example.net>: Feb 20 05:08PM -0500

> can. Just a straight sided metal can, shaped like modern capacitors, but
> bare metal. Some had colored dots on them to identify the leads too.
 
> First, I am thinking that they were geranium types. Is that correct?
 
Germanium, son. Geraniums are the perennials your wife grows in the garden.
 
Fox's Mercantile <jdangus@att.net>: Feb 20 07:14AM -0600

On 2/20/19 6:27 AM, John-Del wrote:
> Interference? I don't know how you can tell that with a digital tuner.
 
You can't.
 
It's like Hatlow's "They'll do it every time."
A bunch of neighbor's pointing at the local amateur radio guy.
Among other comments, "I hear he even interferes with Doc's
diathermy machine.
 
--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
Phil Allison <pallison49@gmail.com>: Feb 20 12:16PM -0800

John-Del wrote:
 
> Interference? I don't know how you can tell that with a digital tuner.
 
** From the circumstances of course.
 
 
> Pixelation, drop outs, freezes, and no signal indications usually mean
> borderline signal to noise ratio.
 
** Or, if intermittent, are clear signs of in-band interference.
 

 
> Get a better antenna, add an amplifier, and carefully redirect it.
> If your TV has a signal level meter (unusual), you can use that.

 
** Mine normally shows over 90% readings for signal level and signal quality - but in the early evening some severe interference and drop outs ( "no signal" message displayed ) are experienced.
 
I reckon it is due to folk turning on their fluoro kitchen lights.
 
 
.... Phil
whit3rd <whit3rd@gmail.com>: Feb 20 12:42PM -0800

On Wednesday, February 20, 2019 at 4:27:40 AM UTC-8, John-Del wrote:
> > building
 
> Interference? I don't know how you can tell that with a digital tuner. Pixelation, drop outs, freezes, and no signal indications usually mean borderline signal to noise ratio.
 
> Get a better antenna, add an amplifier, and...
 
If 'better antenna' means aim-able, or selective of TV frequencies, that's good.
 
Instead of an amplifier, get an ATTENUATOR. It's possible that an out-of-band signal is
overloading the first stages of amplification, before filtering.
When that happens, any pre-amplification just makes the effect worse.
 
<https://www.ebay.com/itm/RadioShack-15-678-75-Ohm-Bidirectional-Attenuator-Improves-TV-UHF-VHF-Reception/401494806442>
 
If attenuation leaves the signal good
but removes the interference, it means (1) the neighbor isn't accidentally clobbering
a TV frequency, and (2) either a selective antenna or a trap or lowpass filter can solve
the problem. Usually cellphone frequencies are too high for TV interference,
and won't go through antenna wires effectively anyhow, but the cell bands
are certainly known and separable from UHF television signals.
Ralph Mowery <rmowery28146@earthlink.net>: Feb 20 03:58PM -0500

In article <mnmp6e9ldvk18vels8m5oq4korfpsgp9tr@4ax.com>, pj@jostle.com
says...
> "no signal". Worse on some channels.
 
> Then, up to now, the interference has stopped, all
> by itself,
 
Is this off the air with an antenna, Direct TV, or cable ?
 
If off the air it may be the leaves on the trees. When they come out,
they tend to absorbe some of the signal.
 
If cable, they should resolve the issue for you. Same for the sat
dishes.
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Digest for sci.electronics.repair@googlegroups.com - 5 updates in 2 topics

micky <NONONOmisc07@bigfoot.com>: Feb 20 10:35AM -0500

In alt.home.repair, on Wed, 20 Feb 2019 17:49:56 +1100, "Rod Speed"
 
>> Digital radios won't work here. They all afaik
>> have a separate momentary-on on/off switch.
 
>Not all of them do, most obviously with car radios.
 
Good point. But the 3 I have do. I'm not buying another unless I was
sure it would get 88.5 and I've tried testing it in the store. Might
work there but not when I get home.
>> FM and the radio was AM. Nonetheless, I turned on a TV and found
>> the channel it was receiving.
 
>Yeah, you can decode FM with an SSB receiver.
 
Very interesting.
 
 
>Likely it was an intermodulation that you were
>receiving and the signal it was intermodulating
>with was what was drifting that dramatically.
 
Very interesting.
 
>> the AC filter capacitors. Everything else still
>> works, even though it's about 85 years old now.
 
>Yeah, they do last well.
 
I may give it a party when it turns 100.
 
thekmanrocks@gmail.com: Feb 20 08:11AM -0800

Ralph Mowery wrote: "as it warms up it should drift to
the station"
 
From which 'side' of the station as selected on the
dial?
devnull <devnull@127.0.0.1>: Feb 20 06:21AM -0500

On 2/19/19 11:27 PM, micky wrote:
> BTW, I've been on 3 trips in the last 2 years totaling 160 days and no
> one has bothered my house at all. I just want to keep it that way.
 
 
 
Life is a constant battle of keeping burglars out of my house and democrats out of my paycheck. Democrats suck!
Chuck <ch@dejanews.net>: Feb 20 10:34AM -0600

On Tue, 19 Feb 2019 18:58:31 -0500, micky <NONONOmisc07@bigfoot.com>
wrote:
 
 
>I can't use radios with electronic tuning because with a timer that
>turns the power off and on, when it comes on, the radio doesn't start
>until someone pushes a button.
If you can find an older Sony Boom Box like the CFD-5 that tune locks,
it won't drift at all. I have one on a timer and the station is always
still locked after I come home from a trip.
tabbypurr@gmail.com: Feb 20 12:31AM -0800

On Tuesday, 19 February 2019 20:16:31 UTC, Phil Allison wrote:
 
> Audio is ELECTRONICS, not sound.
 
> The range of frequencies found in audio electronics extends to frequencies of many MHz. Domestic AM and FM radio deceivers are considered "audio".
 
> Radio microphones are considered "audio".
 
I'm sure we covered this already. The OP did not ask for a scope to do radio work with. He is not servicing hifis.
 
> Faulty ( or badly designed / built ) audio amplifiers may exhibit oscillation upto 50MHz.
 
which even a clunky old 1MHz scope can pick up using an envelope detecting diode.
 
> Digital audio seems to know no bounds.
 
It's the OPs choice whether to spend 3 figures on a scope that can handle every piece of digital audio in existence or 2 figures for one that can do more or less everything he's likely to work on. Given that he's a curious hobbyist, the latter seems more sensible. However, it is the op's choice, not mine or yours.
 
There really is no point covering this ground yet again.
 
 
NT
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Digest for sci.electronics.repair@googlegroups.com - 25 updates in 6 topics

tubeguy@myshop.com: Feb 19 11:13PM -0600

In the 1960s the pocket radios hit the market and were sold everywhere.
I have not opened one of them in years, but I recall the transistors
used in them did not look like more modern types. They had a small metal
can. Just a straight sided metal can, shaped like modern capacitors, but
bare metal. Some had colored dots on them to identify the leads too.
 
First, I am thinking that they were geranium types. Is that correct?
 
Second, I have a very old GE transistor manual (edition 2) (PDF). No
where in there does it mention the case style of them. What is the case
style?
 
Seems those type of transistors came and went quickly. I assume they
were the first generation of transistors.
 
Shortly after, I recall seeing a lot of metal cases that were shaped
more like a hat, with a brim. Those too vanished. And I recall seeing
some of the hat shaped types with a point sticking out of the top. I
always wondered what that point was for???
Allan <a_r_macdonald@hotmail.com>: Feb 20 12:34AM -0800

> more like a hat, with a brim. Those too vanished. And I recall seeing
> some of the hat shaped types with a point sticking out of the top. I
> always wondered what that point was for???
 
Sounds like BC108 series the tab idenified the emitter I think.
tabbypurr@gmail.com: Feb 20 12:42AM -0800

> can. Just a straight sided metal can, shaped like modern capacitors, but
> bare metal. Some had colored dots on them to identify the leads too.
 
> First, I am thinking that they were geranium types. Is that correct?
 
germanium yes.
 
> Second, I have a very old GE transistor manual (edition 2) (PDF). No
> where in there does it mention the case style of them. What is the case
> style?
 
There was TO1, but there were others
 
> Seems those type of transistors came and went quickly. I assume they
> were the first generation of transistors.
 
no, just the 1st generation cheap enough to go into pocket radios
 
> Shortly after, I recall seeing a lot of metal cases that were shaped
> more like a hat, with a brim. Those too vanished. And I recall seeing
 
More than one case type, eg TO39
 
> some of the hat shaped types with a point sticking out of the top. I
> always wondered what that point was for???
 
to kill your opponents of course.
 
 
NT
Look165 <look165@numericable.fr>: Feb 20 10:47AM +0100

I would say it is ACxxx or AFxxx ; they were cased in metal can and
sealed with glass.
The coloured point was indicating the collector.
OCxx were cased in black glass with golden leads.
The so called point (white, red, green or yellow) on top was indicating
the gain range like, A, B, C today.
The second one on bottom was indicating the collector.
 
All were Germanium transistors (take care, ||Vbe||=0.3V).
Then came the 2N4xx.
 
Phil Allison <pallison49@gmail.com>: Feb 20 02:01AM -0800

tub...@myshop.com wrote:
 
.
.
> can. Just a straight sided metal can, shaped like modern capacitors, but
> bare metal. Some had colored dots on them to identify the leads too.
 
> First, I am thinking that they were geranium types. Is that correct?
 
** Yep - made by the Japanese and many others.
 
 
http://oldtube.com/2N408-RCA-used-1pc.jpg
 
 
 
> Second, I have a very old GE transistor manual (edition 2) (PDF). No
> where in there does it mention the case style of them. What is the case
> style?
 
** TO1
 
 
 
> Shortly after, I recall seeing a lot of metal cases that were shaped
> more like a hat, with a brim. Those too vanished.
 
http://oldtube.com/2N508-ETCO-Au-2pcs.jpg
 
 
> And I recall seeing
> some of the hat shaped types with a point sticking out of the top. I
> always wondered what that point was for???
 
 
 
** You are always missing the point .....
 
See here for pics of a great many old semis.
 
http://oldtube.com/Oldtube-semiconductors.htm
 
 
 
.... Phil
Wond <gboot.phil@gmx.com>: Feb 20 03:32PM

On Wed, 20 Feb 2019 02:01:51 -0800, Phil Allison wrote:
 
 
> ** You are always missing the point .....
 
> See here for pics of a great many old semis.
 
> http://oldtube.com/Oldtube-semiconductors.htm
 
Thanks for the link, Phil. What- no CK722!
"Rod Speed" <rod.speed.aaa@gmail.com>: Feb 20 05:49PM +1100

"micky" <NONONOmisc07@bigfoot.com> wrote in message
news:oslp6ehjgeororp691fq6rk5bknptqiej8@4ax.com...
>>only with the old radios tho, not modern digital ones.
 
> Digital radios won't work here. They all afaik
> have a separate momentary-on on/off switch.
 
Not all of them do, most obviously with car radios.
 
 
>>> This is common, I assume.
 
>>No it isnt.
 
> I thought I had at least two radios like this.
 
Looks like you have fluked a couple of duds.
None of my analog radios do that.
 
 
> I know some radios have an AFC switch, so you can get weak stations that
> are close to strong stations, but if there is no AFC switch, I thought
> all FM radios have AFC anyhow.
 
Normally the analog ones do, not needed with digital ones.
 
> even though TV sound in the 50's and until digital is supposed to be
> FM and the radio was AM. Nonetheless, I turned on a TV and found
> the channel it was receiving.
 
Yeah, you can decode FM with an SSB receiver.
 
> frequency. Finally after an hour or two, I reached the end of the band.
> IIRC I switched to the bottom of the next higher band but I couldn't
> find the same transmission.
 
Likely it was an intermodulation that you were
receiving and the signal it was intermodulating
with was what was drifting that dramatically.
 
> Yes, the thing was 30 years old but it was certainly well-designed.
 
Yeah, very decent designs.
 
> I still have the radio and I've only had to replace
> the AC filter capacitors. Everything else still
> works, even though it's about 85 years old now.
 
Yeah, they do last well.
 
tabbypurr@gmail.com: Feb 20 12:48AM -0800

On Wednesday, 20 February 2019 03:51:29 UTC, rbowman wrote:
> > what makes radios drift from the proper tuning?
 
> How old and crappy are your radios? Have you made it up to a
> superheterodyne or are you still in the regenerative era?
 
My 1930s regen doesn't drift after half an hour. But don't look at it sideways.
 
 
NT
tabbypurr@gmail.com: Feb 20 12:51AM -0800

On Wednesday, 20 February 2019 04:40:06 UTC, micky wrote:
 
> still have the radio and I've only had to replace the AC filter
> capacitors. Everything else still works, even though it's about 85
> years old now.
 
AM receivers can receive FM due to a phenomenon called slope detection. It's hardly ideal but can be done. If they can tune to the right frequency.
 
 
NT
Peeler <troll@trap.invalid>: Feb 20 10:04AM +0100

On Wed, 20 Feb 2019 17:49:56 +1100, cantankerous trolling senile geezer Rot
Speed blabbered, again:
 
>> I thought I had at least two radios like this.
 
> Looks like you have fluked
 
Looks like you found another simpleton who hasn't yet realized what's the
matter with you, you fucked up senile Ozzie troll! <BG>
 
--
Richard addressing Rot Speed:
"Shit you're thick/pathetic excuse for a troll."
MID: <ogoa38$pul$1@news.mixmin.net>
devnull <devnull@127.0.0.1>: Feb 20 06:21AM -0500

On 2/19/19 11:27 PM, micky wrote:
> BTW, I've been on 3 trips in the last 2 years totaling 160 days and no
> one has bothered my house at all. I just want to keep it that way.
 
 
 
Life is a constant battle of keeping burglars out of my house and democrats out of my paycheck. Democrats suck!
"pfjw@aol.com" <peterwieck33@gmail.com>: Feb 20 06:10AM -0800

On Tuesday, February 19, 2019 at 6:58:37 PM UTC-5, micky wrote:
> what makes radios drift from the proper tuning?
 
Depending on the vintage of the device:
 
Heat and vibration are the primary culprits. Followed by temperature differences - that is, on a battery set or a low-volt portable tube set, heat from the electronics is not a factor. But a 10-degree change in ambient temperature can cause drift.
 
Then, of course, it can be changes in the time-of-day and environmental effects, local sources of interference and similar. At our summer house, FM is problematic during the day (we are in a valley with at least two mountain ridges between us and the nearest transmitter), but crystal clear at night from several stations. Yes, I know FM is line-of-sight, I am only reporting what is the actual case.
 
"Modern" Digitally tuned devices should not drift at all. And perhaps you should target such devices for your needs while you are away.
 
Peter Wieck
Melrose Park, PA
rbowman <bowman@montana.com>: Feb 20 08:03AM -0700

On 02/19/2019 09:07 PM, danny burstein wrote:
>> superheterodyne or are you still in the regenerative era?
 
> Me, I'm still waiting to upgrade to using a stainless
> steel razor blade for mine...
 
Probably won't work. A Gillette Blue Blade is best but if you are a
manly man a rusty blade or one you've heated with a torch to get a layer
of oxide will do it.
micky <NONONOmisc07@bigfoot.com>: Feb 20 10:32AM -0500

In alt.home.repair, on Tue, 19 Feb 2019 23:17:21 -0500, Ralph Mowery
 
>Just turn the radio on and let it play for half an hour before putting
>it on a timmer.It may come on off frequency ,but as it warms up it
>should drift to the station.
 
That sounds good.
 
Thanks everyone.
Look165 <look165@numericable.fr>: Feb 20 11:02AM +0100

First : check the shield of your antenna cable and the plugs.
Normally telecom use a separate frequency band and your TV has an AGC.
Me, I should contact a technician of this telecom center to see what can
be done.
 
Peter Jason a écrit le 20/02/2019 à 05:53 :
John-Del <ohger1s@gmail.com>: Feb 20 04:27AM -0800

On Tuesday, February 19, 2019 at 11:53:21 PM UTC-5, Peter Jason wrote:
> Are there special filters for this sort of thing,
> and if not how should I frame a complaint?
 
> .
 
Interference? I don't know how you can tell that with a digital tuner. Pixelation, drop outs, freezes, and no signal indications usually mean borderline signal to noise ratio.
 
Get a better antenna, add an amplifier, and carefully redirect it. If your TV has a signal level meter (unusual), you can use that. Many ATSC stand alone boxes did have a signal level utility which is helpful in seeing how much signal you have.
Fox's Mercantile <jdangus@att.net>: Feb 20 07:14AM -0600

On 2/20/19 6:27 AM, John-Del wrote:
> Interference? I don't know how you can tell that with a digital tuner.
 
You can't.
 
It's like Hatlow's "They'll do it every time."
A bunch of neighbor's pointing at the local amateur radio guy.
Among other comments, "I hear he even interferes with Doc's
diathermy machine.
 
--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
tubeguy@myshop.com: Feb 19 11:14PM -0600

I have a small solid state amplifier (receiver) and speakers which I use
for my computer sound. It sounds good. Much better than those amplified
"computer speakers".
 
But I have determined that it is never shut off. When I push the ON-OFF
switch, the sound stops and the pilot LED goes off.
 
The switch is NOT on the line cord, but somewhere inside the circuit.
(No schematic available). I have determined that it's never shut off
completely. When it's turned off, if I put my ears right to the speaker,
I can still hear a very slight hum. My kill-a-watt meter shows it's
always drawing .05 amps when it's turned off.
 
I'm sure that small power draw only costs pennies each month for the
electric, but its still a waste of power, and I prefer ALL electronics
are completely shut off during lightning storms.
 
What the heck kind of a circuit would be used to turn it off, but still
leave it semi-powered? And why????
 
For now, I put it on a power strip, but that strip is not always shut
off, when I am recharging my computer (laptop) battery. I am probably
going to put one of those inline line cord switches on it. But then I
will have to turn on BOTH the line cord switch and the built in one.
(Not that this is a huge problem).
 
I dont understand why anything would be designed this way. There is no
remote control, so it's all senseless.... and poor design. My only guess
is that it stays powered so it can retain radio stations in memory.
(Stereo Digital Synthesize Tuner with push button presets). But I never
use the radio part of it anyhow.
 
If I could find a schematic, I would try to modify the internal
switching. But I have tried to get one, and they do not exist. (This
receiver is probably from the 80s).
 
If it was not for the fact that it has great sound, and a built in
equalizer, I'd probably just replace it. Low powered solid state
receivers or amps are easy to find and cheap to buy.
Rheilly Phoull <rheilly@bigslong.com>: Feb 20 01:23PM +0800


> If it was not for the fact that it has great sound, and a built in
> equalizer, I'd probably just replace it. Low powered solid state
> receivers or amps are easy to find and cheap to buy.
 
Disconnect the switch and use it to interrupt the dc supply?
tabbypurr@gmail.com: Feb 20 12:45AM -0800


> If it was not for the fact that it has great sound, and a built in
> equalizer, I'd probably just replace it. Low powered solid state
> receivers or amps are easy to find and cheap to buy.
 
A low voltage switch is cheaper than a mains one. A tactile or membrane switch is even cheaper.
 
You didn't tell us the power factor. If 1, 0.05A would cost about 5c a year if on 24/7/365. If the pf is 0, it'll cost nothing. It's not worth fitting a mains switch. If it had one it would not be worth operating it.
 
 
NT
"pfjw@aol.com" <peterwieck33@gmail.com>: Feb 20 04:13AM -0800

Brand and age would be quite useful. Back in the days when solid-state "high-powered (+/-60 watts)" amplifiers were new, a fair number of manufacturers would maintain a low-level current through their equipment to avoid thumps and bangs during turn-on - that could damage speakers, again back in the day.
 
Such manufacturers included:
 
AR
Dynaco
Scott
KLH and others.
 
That you are getting a 5-6 watt draw is a bit higher than typical, but within the range. An added benefit is that this process 'kept the capacitors wet' as AR described it, helping their longevity in theory.
 
Peter Wieck
Melrose Park, PA
tabbypurr@gmail.com: Feb 20 12:33AM -0800

On Wednesday, 20 February 2019 01:06:16 UTC, Peter Jason wrote:
 
> Is there a fix; is it a loose connection, dust or
> grit in the works? Should I just flush it out.
 
> Otherwise the radio works well.
 
Sometimes all one need to is twiddle the control back & forth a dozen or 2 times. Sometimes it also needs some cleaner sprayed into the pot. Sometimes that doesn't fix it & it needs its terminals resoldering.
 
 
NT
tabbypurr@gmail.com: Feb 20 12:33AM -0800

On Wednesday, 20 February 2019 08:33:18 UTC, tabby wrote:
 
> > Otherwise the radio works well.
 
> Sometimes all one need to is twiddle the control back & forth a dozen or 2 times. Sometimes it also needs some cleaner sprayed into the pot. Sometimes that doesn't fix it & it needs its terminals resoldering.
 
> NT
 
and rarely the track is worn out.
Look165 <look165@numericable.fr>: Feb 20 10:55AM +0100

Generallly, it comes from a bas contact between the cursor aand the
resistive track (dust or oxyde).
It can also come from a miscontact between this track and the connecting
pad or a "dry solder".
First step : re-solder everything.
Second step : use some KF or equivalent in large quantity inside
(through the opening of the leads).
 
Peter Jason a écrit le 20/02/2019 à 02:06 :
tabbypurr@gmail.com: Feb 20 12:24AM -0800

On Tuesday, 19 February 2019 20:13:45 UTC, Phil Allison wrote:
 
> > Both of those are way above audio, which only extends to 20kHz.
 
> ** While the audible range extends to just a little over 20kHz this has NOTHING to do with the frequencies regularly encountered in *audio electronics*.
 
that is stating the obvious, and we've already covered that.
 
> You are making a common and BIG mistake !!!
 
> A scope suitable for audio electronics needs a BW of at least 10MHz, preferably 50MHz and good waveform resolution - which counts out all the 8 bit "digital" toys being offered today.
 
> .... Phil
 
I've asked you to provide a basis for this claim.
 
 
NT
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